This invention relates to a method and mechanism for constant-measure feed of rod materials to feed rod materials for predetermined length.
Pipes, round bars, reinforcing bars, shape steel and other rod members (hereinafter referred to as rod materials) are formed into standardized lengths. Users produce their desired rod materials by subjecting rod materials they purchased to some machine work such as cutting, bending or the like. Manufacturers of machines, for example, produce many pieces of shape steel with a predetermined length by feeding the shape steel purchased for such predetermined length by suitable conveyor means and repeating cutting operation, and utilize each piece of shape steel for the frame of machines. Further, reinforcing bars for reinforced concrete are processed into various desired shapes, such as the shapes of L, channel or the like by bending them after feeding them for a predetermined length by means of conveyor means.
In a prior art constant-measure feed mechanism for rod materials, rod materials are set directly on conveyor means, and moved distance of the conveyor means itself is sensed. The rod materials are fed for a predetermined length by stopping the conveyor means when it is moved for such predetermined distance. With such conventional construction, tolerances of movement of the conveyor means are accumulated in subjecting the rod materials to a number of machining processes, so that it is difficult to obtain satisfactory processing accuracy. Moreover, if there is any gap between a feed member fixed to the conveyor means and the rear ends of the rod materials, the rod materials will slip on the conveyor means to make the feed distance of the rod materials different from the moved distance of the conveyor means. In setting the rod materials on the conveyor means, therefore, the rear ends of the rod materials must be positively pressed against the feed member to leave no gap therebetween. Thus, the setting of the rod materials on the conveyor means would be a hard task.